Yes it was Trojan, I found traces of it dated 21.02

Oh man, sorry for you forfeit. As you mentioned Trojan was involved into BTC steeling so I guess your wallet lives on Windows . I think now you have three options to make more safe your bitcoin storage. First option is to move to Linux which is in general hostile to trojans. The second is to use hardware wallets which could protect your fund even in the case when computer is compromised providing you check all transactions details before signing them. And the third option is to use offline wallet (aka cold storage) to sign transactions.